InSAR processing using a GPGPU

摘要

General purpose graphical processing units or GPGPUs have emerged in recent years as the power horse behind many large scale computing efforts. For example, the recent unveiling of the world's fastest supercomputer has achieved this feat by utilizing low cost and high performance GPGPUs. Additionally, in the past year the synthetic aperture radar (SAR) community has started to utilize GPGPUs as well. The utilization of GPGPUs to date has been limited mainly to SAR image formation and in this capacity tremendous performance improvements over the same CPU based algorithms have been demonstrated. However, image formation is only one of many necessary steps towards SAR image exploitation. Image registration, filtering, interpolation and interferometric flattening are equally important steps in obtaining many of the desired output products such as coherence change detection (CCD) products and terrain adjusted interferograms. We will demonstrate that by transitioning the entire SAR image exploitation processing chain from image formation through product generation onto a GPGPU, it is possible to achieve more than an order of magnitude in performance improvements. In this paper we will review results presented at last year's SPIE conference regarding SAR image formation and present new results obtained for coherent exploitation of SAR data including CCD and interferometric SAR processing. In addition to presenting these results, we will discuss challenges associated with migration of CPU-based exploitation algorithms to the GPGPU environment, as well as to discuss possible future improvements using these powerful new devices and associated software tools.